International cooperation in the field of patents was initiated in the late nineteenth century to protect and reconcile the interests of inventors, companies and states in the expanding market of innovations. The national patent laws, which often differed, were harmonized and the first international convention for the protection of industrial property was signed in Paris in 1883, even though the nation-states were still competing in this field. The Grand Duchy of Finland was affected by these developments: contemporaries in the Grand Duchy viewed their national patent act of 1876 as outdated, so an updated patent law was approved in 1898. This was problematic, as it triggered a controversy between the Grand Duchy and the Russian Empire on which it depended. This article studies the role of the Diet of Estates in the patent reform of the 1890s and shows how Finnish views about autonomy and the politics of centralization in the Empire clashed in the case of patent law. The article also shows how the Finnish side took advantage of its ties with other countries to bolster its claims. During this period, the Estates acquired legislative prerogatives that had traditionally belonged only to the Emperor. In practice, this fact strengthened the autonomy of the country.